Pump-piston



' (NoModel) L. L. BIGELOW.

PUMP PISTON.

No. 279,318. Patented June 12,1883.

35 water rushes up around the outside edge of UNITED STATES LEANDER L. BIGELOW,

PATENT OFFICE.

OF OORNVILLE, MAINE.

PUMP-PISTON.

SPECIFICATION forming part of Letters Patent No. 279,318, dated June 12, 1883.

Application filed January 29,1883. (No model.)

To all whom it may concern Be it known that I, LEANDER L. BIGELOW, a citizen of the United States, residing at Oornville', in the county of Somerset and State of Maine, have invented certain new and useful Improvements in Pump-Pistons; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this specification.

My invention relates to upper boxes for pumps, and particularly for wooden pumps.

It consists in a box or piston so constructed that when it goes down it allows the water to flow up around the edges of the box, and when it comes up the edges of the box expand and fill the tube of the pump.

In the drawings, Figure 1 shows a perspective View. Fig. 2 shows a longitudinal section through a: a: 00 of Fig. 1.

O is a cone-shapedpiston, of wood, to which is attached the pump'rod B. The piston C is covered with stiff leather, or rubber, or other flexible material, A, which extends some distance above the top of the cone 0, forming a lip or flange, A. Two slits, a a, are made in the flange A from the top down to'the top of the cone 0, so that the two halves of the flange A are independent pieces. When the box or piston is forced down in the water-tube D, the

the box 0. The flange A is pressed inward from all sides, and since it is flexible the edges at a a lap by each other, thus contracting the diameter of the box and allowing the water to pass between it and the inside of the tube freely, as shown by the dotted lines in Fig. 2. As the box comes up, the weight of water on top causes the flange A to spread out against the side of the water-tube D, conforming to any inequalities which may exist in the surface of the tube. As the surface of the tube wears away, the flange A continues to expand correspondingly until it assumes a nearly horizontal position.

It is evident that the box will always be tight as long as the flange remains large enough to fill the tube, and that it thus has advantages over the non-expansible box.

My box may be constructed in a variety of ways. For instance, the entire lower portion may be of wood or other suitable material, and the flange A alone constructed of leather, and secured to its upper edge by a number of means.

' I claim- The conical piston 0, provided with a covjects above the said cone, and is slit at a, subg stantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

LEANDER L. BIGELOW. Witnesses: S. W. BATES, H. D. Barns.

ering, A, the flexible flange A of which pro- 

